* Created a double linked list to hold all user records. Hash tables are
great, but sometimes you just have to go through all records.
* Refuse to actively link to bots with a negative priority. Incoming
connections from these bots will still be acceppted.
* Refuse partyline logins from bots. Bots usually don't have a password
set, so that might be exploitable.
* Ping connected bots if they haven't sent anything for 5 minutes.
* Started to structure the user settings and documented it with a Doxygen
page.
* Added autolinking for bots based on a priority. See botnet_autolink()
documentation for details.